Need Help w/ KLX 300

I have a California stock 03 KLX300r, and I recently installed a Dynojet kit on it. I drilled out the hole with the drill bit provided and installed the new needle with the clip in grove #4. I also put in a 132 main jet and turned out the mixture screw 2 1/2 turns. Once I hit the trails, I noticed that my bike sounds horrible and low altitudes. It idles very iregular and stalls when I come to a stop and is hard to start. I tried moving the idle screw but it doesn't change the idle, unless I mess with it at the top of the trails. Once I get to the top of the trails, the bike idles and sounds great, aswell as performs great. In terms of Mods, I removed the airbox lid, and the exhaust cap, and kept the stock exhaust. I looked at a map and it looks like the trails I ride are from 2000 feet to 4500 feet.

My question is, should I change the clip on the needle or the Main jet size or do something else to it.

Thanks :naughty:

Do you have an aftermarket header? The specs you quoted are for a KLX with an aftermarket header and hi flow air filter if I'm not mistaken. Have you talked directly with dynojet? They were very helpful when I had a question.

I will try talking to them, and my header pipe is stock. The stage 2 kit with the needle and jet is for a stock bike with the airbox lid removed and the end cap off, according to the directions. Thanks for the help

This may help you determine what changes need to be made.

The pilot screw affects from idle to about 1/4 of the slide opening. The needle (clip position) affects from 1/4 to 3/4 of the slide opening, and the main jet affects from 3/4 to wide open. These do have some overlap. And please take notice that I said slide opening, NOT throttle position. The slide position is controlled by the vacuum created in the carb venturi.

Ride on


hey Billp and Brewster

you guys helped me in the past with a jetting problem. From what Racer9 is saying, its sounds like his bike is running on the rich side ,if that being the case

wouldn't the bike run worse at higher elevation. Any thoughts on this . I'm still

learning this jetting thing.

Higher elevation = Less air. Less air = More gas. More gas = richer

So, yes you are right.

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